Touch systems are well known in the art and many variations exist. In all cases, touch systems include a touch panel having a touch surface on which contacts are made using a pointer. Pointer contacts with the touch surface are detected and are used to generate corresponding output that represent the positions on the touch surface where contacts are made. The contact position output is typically fed to a computer that executes one or more applications programs. The computer generates image data that is used to present images on the touch surface. The computer uses the contact position output to update the image data and thus, the images presented on the touch surface. In this manner, the images presented on the touch surface are updated to reflect the activity of the pointer on the touch surface.
For example, U.S. Pat. No. 5,448,263 to Martin, assigned to the assignee of the present invention, discloses a passive analog resistive touch panel coupled to a computer. The computer provides image data to a projector that projects images onto the touch surface of the touch panel. The touch panel includes a tool tray that supports a plurality of differently coloured pens. When a user contacts the touch surface either with a finger, other pointer or a pen, the touch panel outputs signals representing the contact position on the touch surface. The contact position data is conveyed to the computer and is mapped to the computer display. If a finger or other pointer is used to contact the touch surface, the touch system operates in a pointer mode and the contact position data is treated as a mouse event. This allows the user to operate the computer in a manner similar to using a computer mouse i.e. select menus, manipulate objects etc. simply by contacting the touch surface. If a pen is lifted from the tool tray and is used to contact the touch surface, the touch system operates in an ink mode and the contact position data is recorded as writing or drawing.
When the computer is running an applications program in a Windows environment, a computer desktop image is presented on the touch surface that includes icons representing the various applications programs available for selection. When an icon is selected, a window for the selected applications program is opened. The window typically includes a frame, one or more tool bars, optional scroll bars and an active area surrounded by the frame, tool bars and scroll bars. As mentioned above, in the pointer mode, contacts on the touch surface are treated as mouse event input to the computer desktop. The computer in response to the mouse event input controls the computer desktop or selected applications program according to the touch panel output and updates the image data conveyed to the projector for display to reflect the pointer activity.
In the ink mode, an acetate image identical to the computer desktop image overlies the computer desktop image to provide a surface on which ink can be drawn. When a pen contacts the touch surface, the contact position data is treated as writing or drawing (herein referred to as “writing”). In this case, the computer updates the image data conveyed to the projector for display so that the writing is displayed on the acetate image.
In order to interpret writing when the touch system is operating in the ink mode, the computer can be conditioned to execute a handwriting recognition routine. As a result, writing on the touch surface can be translated into text. In many circumstances, however, the writing on the touch surface is not clear making translation difficult. To enhance text recognition, several prior systems have been considered.
For example, U.S. Pat. No. 5,963,666 to Fujisaki et al. discloses a confusion matrix for aiding in the recognition of handwritten text. Handwritten characters input into a data field of an applications program are recognized and assigned a cluster code. The string of characters is characterized by the cluster codes of the individual characters. The cluster codes of the string are compared with strings of cluster codes representing words in a dictionary. All or some of the matching words are displayed to the user, from which a selection can be made.
U.S. Pat. No. 5,367,453 to Capps et al. discloses a word correction system and method. Ink objects entered into a computer system with a pointer are recognized as word objects and are displayed. If a correction request is entered by a user pertaining to a displayed word object, a list of alternative words for the word object are displayed. The user can select an alternative word from the list to replace the displayed word object.
U.S. Pat. No. 5,329,609 to Sanada et al. discloses a word recognition system including a dictionary order sorter that re-sorts character strings of recognition candidates stored in a high-ranking candidate memory in the order of distance into the dictionary. When a sort termination signal is received, character strings of recognition candidates stored in the memory are displayed together with their ranking numbers.
Although these prior systems assist in recognizing handwriting, these systems are limited in that they simply provide the results of a fixed interpretation. As will be appreciated alternative systems to enhance the manner by which writing is interpreted are desired.
It is therefore an object of the present invention to provide a novel system and method for providing gesture suggestions to enhance interpretation of user input.